Why does ‘Tonic Water’ glow in the dark?

Things glowing in the dark can remind you of your childhood days when you used to experiment with your friends. This may seem like a fun thing to do, but it’s actually true! If you were to look at a gin and tonic (or vodka and tonic, or anything with tonic, for that matter) under ultraviolet light, you might be surprised to see it glow and you might naturally wonder what produces the eerie effect.

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